环境和工具
服务端电脑IP：192.168.1.130
客户端电脑IP：192.168.1.120
1、在服务端电脑运行IoTClientTool
2、运行Wireshark
3、在客户端电脑运行IoTClientTool
4、Wireshark得到如下报文
报文分析，plc的连接
我们看到上面连接西门子plc抓取到了八条报文。其中有tcp的三次握手、和对最后一次响应的回复，然后就是西门子特有的两次初始化指令的请求和响应。
两次初始化指令
不同型号的西门子plc有不同的初始化指令，同型号的指令固定不变。
代码实现对plc的连接
//直接是Wireshark抓取到的报文数据
var Command1 = new byte[22]
{
0x03,0x00,0x00,0x16,0x11,0xE0,0x00,0x00,
0x00,0x01,0x00,0xC1,0x02,0x10,0x00,0xC2,
0x02,0x03,0x00,0xC0,0x01,0x0A
};
var Command2 = new byte[25]
{
0x03,0x00,0x00,0x19,0x02,0xF0,0x80,0x32,
0x01,0x00,0x00,0xCC,0xC1,0x00,0x08,0x00,
0x00,0xF0,0x00,0x00,0x01,0x00,0x01,0x03,0xC0
};
Socket socket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
socket.Connect(new IPEndPoint(IPAddress.Parse(ip), port));
//第一次初始化指令交互
socket.Send(Command1);
var head1 = SocketRead(socket, SiemensConstant.InitHeadLength);
SocketRead(socket, GetContentLength(head1));
//第二次初始化指令交互
socket.Send(Command2);
var head2 = SocketRead(socket, SiemensConstant.InitHeadLength);
SocketRead(socket, GetContentLength(head2));
对寄存器的读取
我们在客户端电用IoTClientTool读取地址V2634，抓取到包
我们可以看到其中很多都是固定的数据，如版本号、协议id等等。所以，我们可以以此规律获取对应的指令格式
protected byte[] GetReadCommand(byte type, int beginAddress, ushort dbAddress, ushort length)
{
byte[] command = new byte[31];
command[0] = 0x03;
command[1] = 0x00;//[0][1]固定报文头
command[2] = (byte)(command.Length / 256);
command[3] = (byte)(command.Length % 256);//[2][3]整个读取请求长度为0x1F= 31
command[4] = 0x02;
command[5] = 0xF0;
command[6] = 0x80;//COTP
command[7] = 0x32;//协议ID
command[8] = 0x01;//1 客户端发送命令 3 服务器回复命令
command[9] = 0x00;
command[10] = 0x00;//[4]-[10]固定6个字节
command[11] = 0x00;
command[12] = 0x01;//[11][12]两个字节，标识序列号，回复报文相同位置和这个完全一样；范围是0~65535
command[13] = 0x00;
command[14] = 0x0E;//parameter length（[17]-[30]都为parameter刚好14也就是0x0E）
command[15] = 0x00;
command[16] = 0x00;//data length
command[17] = 0x04;//04读 05写
command[18] = 0x01;//读取数据块个数
command[19] = 0x12;//variable specification
command[20] = 0x0A;//Length of following address specification
command[21] = 0x10;//Syntax Id: S7ANY
command[22] = 0x02;//Transport size: BYTE
command[23] = (byte)(length / 256);
command[24] = (byte)(length % 256);//[23][24]两个字节,访问数据的个数，以byte为单位；
command[25] = (byte)(dbAddress / 256);
command[26] = (byte)(dbAddress % 256);//[25][26]DB块的编号
command[27] = type;//访问数据块的类型
command[28] = (byte)(beginAddress / 256 / 256);
command[29] = (byte)(beginAddress / 256);
command[30] = (byte)(beginAddress % 256);//[28][29][30]访问DB块的偏移量
return command;
}
读取数据
public Result<byte[]> ReadString(string address, ushort length)
{
Connect();
var result = new Result<byte[]>();
//发送读取信息
var arg = ConvertArg(address);
byte[] command = GetReadCommand(arg.TypeCode, arg.BeginAddress, arg.DbBlock, length);
result.Requst = string.Join(" ", command.Select(t => t.ToString("X2")));
var dataPackage = SendPackage(command);
byte[] requst = new byte[length];
Array.Copy(dataPackage, 25, requst, 0, length);
//Array.Copy(dataPackage, dataPackage.Length - length, requst, 0, length);
result.Response = string.Join(" ", dataPackage.Select(t => t.ToString("X2")));
result.Value = requst;
return result;
}
对寄存器的写入
我们在客户端电用IoTClientTool对地址V2634写入值666，抓取到包
我们可以以此规律获取对应的指令格式
protected byte[] GetWriteCommand(byte type, int beginAddress, ushort dbAddress, byte[] data)
{
byte[] command = new byte[35 + data.Length];
command[0] = 0x03;
command[1] = 0x00;//[0][1]固定报文头
command[2] = (byte)((35 + data.Length) / 256);
command[3] = (byte)((35 + data.Length) % 256);//[2][3]整个读取请求长度
command[4] = 0x02;
command[5] = 0xF0;
command[6] = 0x80;
command[7] = 0x32;//[4]-[7]固定数据
command[8] = 0x01;//1 客户端发送命令 3 服务器回复命令
command[9] = 0x00;
command[10] = 0x00;
command[11] = 0x00;
command[12] = 0x01;//[9]-[12]标识序列号
command[13] = 0x00;
command[14] = 0x0E;
command[15] = (byte)((4 + data.Length) / 256);
command[16] = (byte)((4 + data.Length) % 256);//[15][16]写入长度+4
command[17] = 0x05;//04读 05写
command[18] = 0x01;//写入数据块个数
command[19] = 0x12;
command[20] = 0x0A;
command[21] = 0x10;//[19]-[21]固定
command[22] = 0x02;//写入方式，1是按位，2是按字
command[23] = (byte)(data.Length / 256);
command[24] = (byte)(data.Length % 256);//写入数据个数
command[25] = (byte)(dbAddress / 256);
command[26] = (byte)(dbAddress % 256);//DB块的编号
command[27] = type;
command[28] = (byte)(beginAddress / 256 / 256 % 256); ;
command[29] = (byte)(beginAddress / 256 % 256);
command[30] = (byte)(beginAddress % 256);//[28][29][30]访问DB块的偏移量
command[31] = 0x00;
command[32] = 0x04;//04 byte(字节) 03bit（位）
command[33] = (byte)(data.Length * 8 / 256);
command[34] = (byte)(data.Length * 8 % 256);//按位计算出的长度
data.CopyTo(command, 35);
return command;
}
写入数据
public Result Write(string address, byte[] data)
{
if (!socket?.Connected ?? true) Connect();
Result result = new Result();
Array.Reverse(data);
//发送写入信息
var arg = ConvertArg(address);
byte[] command = GetWriteCommand(arg.TypeCode, arg.BeginAddress, arg.DbBlock, data);
result.Requst = string.Join(" ", command.Select(t => t.ToString("X2")));
var dataPackage = SendPackage(command);
result.Response = string.Join(" ", dataPackage.Select(t => t.ToString("X2")));
return result;
}
IoTClient中S7-200SmarTcp协议的使用
安装
Nuget安装 Install-Package IoTClient
或图形化安装
使用
//1、实例化客户端 - 输入正确的IP和端口
SiemensClient client = new SiemensClient(SiemensVersion.S7_200Smart, "127.0.0.1",102);
//2、写操作
client.Write("Q1.3", true);
client.Write("V2205", (short)11);
client.Write("V2209", 33);
//3、读操作
var value1 = client.ReadBoolean("Q1.3").Value;
var value2 = client.ReadInt16("V2205").Value;
var value3 = client.ReadInt32("V2209").Value;
//4、如果没有主动Open，则会每次读写操作的时候自动打开自动和关闭连接，这样会使读写效率大大减低。所以建议手动Open和Close。
client.Open();
//5、读写操作都会返回操作结果对象Result
var result = client.ReadInt16("V2205");
//5.1 读取是否成功（true或false）
var isSucceed = result.IsSucceed;
//5.2 读取失败的异常信息
var errMsg = result.Err;
//5.3 读取操作实际发送的请求报文
var requst = result.Requst;
//5.4 读取操作服务端响应的报文
var response = result.Response;
//5.5 读取到的值
var value3 = result.Value;